Single Stage HVAC Zone Systems are….Not as Good?

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We kind of said this is a this is like a Incomplete system almost it's just Missing that extra step that will give It that perfect load matching because You're right the speeds don't change Because of Any Sense of what the temperature or Humidity or enthalpy is in the duct work The speeds chain based on what you put On the thermostat and whatever criteria You set up like I set it up on the Zone Board so it's a little bit better for me Than it would be with a normal Thermostat you might change the cycle Rate which was a big thing with Everybody talking about Bosch lower the Cycle rate I have the ewc this is on YouTube Somewhere my gosh if I could Look it up I'd put a link to it in the Live chat but uh if you look at ewc Board install I'm sure the video pops up It's like an hour long I mean I did Everything was included on this and I Set it up so that it took a long time to Go into second stage and it won't go Into second stage unless two of the Zones are calling which I really really Like the weighted Zone controls I think You almost have to have that And I agree with two stage or higher you Don't want uh single stage with zoning Anymore I mean that's Unless you it's just super budget where You have to have a zone system because

You're trying to Two floors with one system which I don't See a lot of people doing that anymore With single stage units it was imperfect It really was it was doable but the Lifetime of the system was diminished And you're already going to have issues With like the contactor because it's Going to be on and off all the time you Have to put a delay in there but a lot Of times there is a delay but still it's On off on off on off all the time It's hard on the system it really is if It's single stage it's even harder Because it's getting colder and colder Because you're taking bypass air because You can't just have no bypass on single Stage unless you compensate with larger Duct work and then you're going to have A potential velocity issue as well It's really hard to do that it's really Hard because when both zones open just Imagine it you have a zone system on Single stage you have a blower blowing 1200 CFM of air it's a three ton system Let's say so instead of having what you Normally would have around here which is Two 12 inch round ducts that come off a Plenum let's say Let's say you have to handle 1200 CFM But you don't want to give it like an 18 Inch duct coming off of there because The velocity will die Let's say you make 14 inch

14 inches your compensation it's still Going to be loud because 1200 through 14 Inches way too much But If you go any bigger than that when both Zones call and you have let's say two 16s on there The velocity is going to die it's just Going to be so slow and you're not going To have to throw from your registers You're not going to have that delivery To every duck like you need If you have a trunk system that has Various takeoffs on it and you're trying To get an even velocity to every take Off you have to reduce that trunk Periodically and if you change the Dynamics of duct design to alleviate This sort of zoning issue it's going to End up biting in the face So definitely don't do that don't do That

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